After a four-year absence due to the global pandemic, the aerospace industry returned in force to the Paris Air Show, which was marked not just by 1,260-plus orders and options for new aircraft, but also by a flood of product, procurement and partnership deals focused on reducing the sector’s impact on the environment. The event was also thick with news of zero-emission aircraft and propulsion systems, technology breakthroughs promising higher efficiency and lower emissions, and research and development programmes to refine or explore paths to more sustainable aviation. An order by India’s largest airline, IndiGo, for 500 Airbus A320 and 321 neo jets to accommodate huge growth plans beyond 2030, reinforced forecasts that the global commercial fleet will double in size over the next 20 years.

Multiple commitments and technology advances were announced for the evolving electric aviation sector, most with certification and entry-into-service targets between 2025 and 2030. Miami-based AeroLease announced it had signed a letter of intent (LOI) to acquire 50 Eviation Alice electric commuter planes, while Netherlands-based start-up Maeve Aerospace unveiled a revised version of its proposed 44-seat Maeve 01 all-electric aircraft, to be powered with four 1.2 Mw electric motors. Maeve is aiming for certification in 2028 and entry into commercial service in 2030.

French start-up Aura Aero confirmed commitments and collaborations in Europe, the US and Africa for its ERA electric thrust aircraft, which will be offered in passenger and freight configurations. Maltese executive fleet operator Elit’ Avia and French regional carrier Pan Europeene signed LOIs for a combined 12 planes. Additionally, Utah-based freight airline Alpine Air Express signed a memorandum of understanding (MoU) to assist Aura Aero in gaining US certification for the ERA and Gabon-based AfriJet signed a MoU, which, while not specifying details, the airline’s CEO, Marc Gaffajoli, described as “for us, the most plausible and mature solution.”

Marseille-based airframer Daher, together with Airbus and Safran, exhibited for the first time their EcoPulse aircraft, a hybrid-electric distributed propulsion testbed, which will rely on a single independent electrical source to power multiple engines. Based on Daher’s TBM aircraft platform, the EcoPulse has six wing-mounted e-propellers provided by Safran, and two power sources – a Safran gas turbine and a battery pack supplied by Airbus. The demonstrator will begin flight testing later this year as part of a programme to define, develop and deliver a hybrid-powered plane to market by 2027.

Another French start-up, Beyond Aero, unveiled its four-passenger BYA-1 hydrogen-electric jet, while the Volt Aero Cassio 330, a 4-5 seat hybrid-electric aircraft, was also displayed ahead of its first flight in the coming weeks.

US-based electric powertrain developer MagniX said it would soon start converting a De Havilland Dash 7 aircraft into a zero-emission testbed, replacing two of its four Pratt and Whitney Canada PT6A engines with new MagniX 650 electric motors, and a pair of 450kwH battery packs. Another electric propulsion developer, Wright Electric, announced that ground trials of its new aerospace motor-generator had delivered 1 Megawatt (1,300 horsepower) of energy, enabling it to be used as a turbogenerator or auxiliary power unit for high altitude commercial or defence applications.

Airbus announced a research and development partnership with Geneva-based STMicroelectronics to explore the development of lighter, more efficient power electronics required for future hybrid-powered aircraft and all-electric air taxis. They will focus on wide bandgap Silicon Carbide and Gallium Nitride semiconductor materials, which have better electrical properties than conventional conductors such as silicon.

Rolls–Royce revealed it was ready to test its first small gas turbine, developed as a turbogenerator system for novel propulsion aircraft including electric air taxis, and hybrid-electric commuter planes seating up to 19 passengers. Additionally, regional jet maker Embraer announced a joint venture with Japanese electric motor manufacturer NIDEC to develop propulsion systems for eVTOL aircraft, with Embraer’s air taxi division Eve Air Mobility the launch customer.

Hydrogen propulsion developer ZeroAvia announced multiple deals, the largest of them an agreement to deliver 250 hydrogen-electric ZA2000 engines for 40-80 seat turboprop conversions to California-based Flyshare, which will launch a new airline, Air Cahana, on the west coast. UK-based lessor Monte also firmed a previously-provisional order for 100 ZA 600 powertrains for 9-19 seat aircraft, while French lessor Green Aerolease signed an MoU to acquire an unspecified number of ZA 600 units.

ZeroAvia also revealed that in tests with MHIRJ, the type certificate holder for CRJ regional jets, “clear applications” had been identified to retrofit regional jet aircraft with hydrogen-electric propulsion systems. The initial aircraft suitable for conversion to ZeroAvia’s proposed ZA 2000RJ powertrain would be a CRJ 700 aircraft, though the technical study also validated conversions of other in-service CRJ-series jets, including the CRJ 500 and 990 models.

Another zero-emission start-up, Sydney-based Dovetail Electric Aviation, announced a partnership with HTWO, the hydrogen power division of Korea’s Hyundai Motor Company, to test a hydrogen-electric powertrain for regional aircraft, with a view to commencing test flights as early as next year.

Deutsche Aircraft revealed the first metal was being cut for the prototype of its 40-seat D328eco regional airliner, a 100% SAF-compatible turboprop, which is scheduled for its first flight in 2025 and targeting entry into service by 2026, while at the opposite end of the scale US-based Jet Zero revealed its Z4 blended wing concept, targeted as a replacement for mid-market aircraft including the Boeing 767 and 787-8, with fuel burn savings of up to 50%.

The Airbus research arm UpNext announced a new test programme to investigate the replacement of a fossil-fuelled auxiliary power unit with a hydrogen fuel cell system to power non-propulsive aircraft functions including air conditioning, cabin lighting and avionics. An A330-200 jet will be retrofitted for the programme, taking to the air by late 2025.

Airbus also signed a MoU with US-based SAF producer LanzaJet to advance the construction of facilities to produce sustainable aviation fuel using LanzaJet’s alcohol-to-jet technology, while global energy company Sasol and Topsoe, a specialist in carbon reduction technologies, agreed to form a 50-50 joint venture to develop, build, own and operate new SAF plants, and market renewable fuels. E-fuel producer Twelve also used the Paris show to announce plans for SAF production from CO2 and renewable energy at a new plant to be built in the US state of Washington.

United Airlines Ventures revealed that another seven to eight partners would join its Sustainable Flight Fund within the next two months, and foreshadowed investment in new SAF offtake deals as producers built renewable fuel capacity.

On the eve of the Paris Air Show, seven chief technology officers from major aviation manufacturers released a statement committing to “supporting policies that increase the supply of SAF while ensuring a consistent and predictable demand through harmonised global measures.”

The CTOs of Airbus, Boeing, Dassault Aviation, GE Aerospace, Pratt & Whitney, Rolls-Royce and Safran added: “We are unified in the proposition that our industry has a prosperous and more sustainable future, and that we can make it happen through the near-term implementation of lasting industry-wide and globalised harmonised policies.”

Photo: French President Emmanuel Macron visits Aura Aero display at the Paris Air Show

Airbus has announced a range of new international agreements to help progress the preparedness of airports to deliver hydrogen fuel. The company has signed a Memorandum of Understanding (MoU) with Linde, a global industrial gases and engineering group, to jointly investigate hydrogen production, airport storage and integration of refuelling into existing ground handling operations. Both companies will define and undertake pilot projects at multiple airports worldwide from early next year. Airbus has also announced agreements with European LCC Wizz Air to explore the potential for hydrogen-powered aircraft operations and with Suzhou Industrial Park in eastern China to establish the Airbus China Research Centre, which will study advanced technologies including hydrogen energy infrastructure. And it has signed a Memorandum of Cooperation (MoC) with airports trade body ACI Europe to help ensure sufficient infrastructure is in place to support zero emission aircraft technologies, including hydrogen fuel. In addition to their hydrogen partnership, Airbus and Linde will also investigate the potential of power-to-liquid (PtL) fuels, reports Tony Harrington. Meanwhile, Deutsche Aircraft has signed a MoU with Sasol ecoFT on PtL technology collaboration.

Hydrogen propulsion is rapidly evolving as an option for short to medium haul air transport, with Airbus planning to introduce a family of hydrogen-powered aircraft from the mid-2030s. In 2020, the company announced its ZEROe concept for hydrogen-powered aircraft, and launched ‘Hydrogen Hub at Airports’, a programme designed to drive research into the infrastructure needed to transition to low carbon airport operations. Agreements have since been signed with partners and airports in France, Italy, South Korea, Japan and Singapore. 

The global partnership between Airbus and Linde expands a cooperation agreement the companies signed in Singapore in February. “We are advancing well with hydrogen as an important technology pathway to achieve our ambition of bringing a zero-emission aircraft to market by 2035,” said Sabine Klauke, Airbus CTO. “That’s why we are working closely with partners like Linde, who have decades of experience and expertise worldwide in the storage and distribution of hydrogen.” 

Linde’s VP Clean Energy, Philippe Peccard, welcomed the global expansion of his company’s collaboration with Airbus. “By harnessing both companies’ competencies, we are well positioned to collaborate with airports and government authorities in the development of viable concepts for sustainable airport hubs based on hydrogen,” he said.  

Airbus also continues to enter hydrogen research partnerships with airlines, most recently joining the Hungarian low-cost carrier Wizz Air, a major Airbus customer, to evaluate logistics and opportunities for the new fuel. Under the terms of an MoU, the two will explore the potential of hydrogen-powered operations for ultra-low-cost airlines, specifically focusing on the impact hydrogen aircraft will have on Wizz Air’s fleet, operations and infrastructure. The companies will examine specific aircraft characteristics, including flight range and refuelling time, and how these factors might impact the airline’s network, flight scheduling, ground bases and operations at airports.

“We believe that growth and sustainability are not mutually exclusive, with leading-edge new technology paving the way to more sustainable air travel,” said Johan Eidhagen, Wizz Air’s Chief People and ESG Officer. “This momentous agreement with Airbus will advance sustainable aviation across the globe through development of ultra-efficient operations and business models of the future.”  

Glenn Llewellyn, Airbus VP Zero Emission Aircraft, said such partnerships with airlines were vital for the company in its development of zero emission aircraft. “Understanding airline fleet and network performance enables us to better define the architectural characteristics for future ZEROe aircraft as well as the impact on airports, ground support and route network,” he said. “We are very pleased to have Wizz Air on board to collaborate on the ongoing research and development into the requirements for hydrogen aircraft operations within a hydrogen-powered aviation ecosystem.”

Airbus said its collaboration with ACI Europe further aims to develop the hydrogen ecosystem by preparing the associated supporting airport infrastructure and bring these to market. It will promote the set-up of technical standards and guidance facilitating the uptake of SAF, hydrogen and electric-powered aircraft, as well as make proposals for the emergence of a policy and regulatory framework.

The establishment of a new research centre in Suzhou will provide research services in advanced manufacturing, hydrogen energy infrastructure, sustainability, electrification and other new technologies, reports China Daily. Operations are due to start in 2023.

While Airbus and Linde plan to also investigate power-to-liquid fuels, another aviation partnership has announced plans to progress the development of PtL and support its certification as a sustainable aviation fuel. Germany’s Deutsche Aircraft and South African chemicals and energy group Sasol ecoFT have signed an MoU to progress technology to produce green hydrogen-based PtL SAF, as part of the aircraft manufacturer’s D328eco aircraft programme.

Deutsche Aircraft is targeting 2026 for certification of this new regional aircraft, which it wants to be compatible with PtL as well as other certified SAF and regular kerosene. Fischer-Tropsch technology specialist Sasol ecoFT converts gasified biomass feedstocks or captured carbon dioxide into liquid fuels. The company is experienced in coal-to-liquid conversion, which is chemically similar to PtL SAF, and will begin their partnership by testing the compatibility of blended synthetic fuels produced through this process.

“Sasol ecoFT and Deutsche Aircraft stand at the beginning of a decarbonisation journey,” said Regina Pouzolz, Head of Sustainability for Deutsche Aircraft. “We both have products originally designed in the age of fossil fuels. Together we can develop rapid solutions to combat climate change by improving our products while building on our heritage and expertise.”

Sasol ecoFT VP Helga Sachs added: “Joining forces between aircraft manufacturers and fuel producers is vital if we want to ensure that aviation becomes sustainable, while enjoying the highest possible safety standards. We are extremely excited about the partnership with Deutsche Aircraft as we take a holistic approach to climate-neutral aviation by looking at the whole value chain from fuel production up to aircraft system level.” 

Photo: Sabine Klauke, Airbus CTO and Philippe Peccard, VP Clean Energy, Linde, sign cooperation agreement at the ILA Airshow in Berlin

MRO and technical aircraft services provider Lufthansa Technik has joined with Hamburg Airport in an initiative to design and test maintenance and ground processes for handling liquid hydrogen (LH2) that is expected to be used in powering future aircraft. The two-year research project, which has received funding from the city of Hamburg, will also involve the German Aerospace Center (DLR) and the Center for Applied Aeronautical Research (ZAL). As part of the project, a decommissioned Airbus A320 aircraft will be converted into a stationary, fully functional field laboratory equipped with LH2 infrastructure at Lufthansa Technik’s base at the airport. In the first phase, due to be completed by the end of this year, the partners will identify areas for developing and elaborating the concept for subsequent testing with the aim next year to jointly implement a pioneering demonstrator to be operational by 2022. Elsewhere in Germany, start-ups Deutsche Aircraft and H2FLY have agreed to work together on developing hydrogen fuel cell technology for commercial regional aircraft.

As well as contributing to the Hamburg project operational expertise in the maintenance and modification of commercial aircraft, Lufthansa Technik says it is also able to incorporate a customer perspective through its airline customers. In parallel, DLR will be creating a virtual environment to achieve digital and highly accurate mapping of the defined fields of development and says the platform will aim to provide inspiration for the next generation of aircraft through parameterised and highly accurate virtual models. DLR adds that it has long-standing and cross-sector experience with hydrogen.

“The aircraft of the future are lighter, more efficient and fly with alternative propulsion concepts, and hydrogen will play an important role in this. We need to learn – promptly and in detail – the ground requirements for aircraft and their maintenance of real-world operation with hydrogen,” explained Dr Markus Fischer, DLR Deputy Board Member Aeronautics. “In the project, we are using this data and experience to develop digital models for ground processes that can then be used directly in the design of future-oriented and yet practical aircraft configurations.”

Hamburg Airport CEO Michael Eggenschwiler said climate-friendly flying with hydrogen technology was only possible through a perfect fit with ground infrastructure. “Close coordination is required here and we as an airport are pleased to be able to contribute our know-how to this important project, from questions over storage and distribution to the refuelling process on the apron.

“At the airport, we also rely on hydrogen as a technology of the future for our ground transport. This project offers us the chance to identify and make the best possible use of synergy effects between gaseous hydrogen, such as that used for refuelling our baggage tractors, and liquid hydrogen for aircraft refuelling.”

ZAL, meanwhile, will provide its know-how in fuel cell technology and digital process mapping. “The development of a field laboratory and a digital twin are important components of Hamburg’s Green Aviation Technology Roadmap,” said ZAL CEO Roland Gerhards. “They were developed together with the members of the Hamburg Aviation Cluster last year to strengthen Hamburg’s competence in research and development in a European context.”

The project is the largest single initiative in a City of Hamburg’s special programme to mitigate the economic impact of the coronavirus pandemic on the aviation industry.

“Hamburg is not just one of the three largest aviation clusters in the world – last year the city also developed a clear vision of becoming a major hydrogen metropolis,” said Michael Westhagemann, the city’s Senator for Economics and Innovation. “The port, the energy sector, industry and the entire mobility sector are involved and are preparing for this groundbreaking technology.

“With this project, we are now also making an essential contribution to the transformation of aviation into a climate-neutral mobility solution of the future. The clear goal is to build up a hydrogen economy in Hamburg that will occupy a leading position internationally.”

Responded Lufthansa Technik CEO Dr Johannes Bussmann: “I am very grateful for the foresight of the city of Hamburg and its generous funding of this project.

“There is no alternative to the transformation of our industry towards climate-neutral aviation. With this project, we want to tackle this enormous technological challenge at an early stage – for the entire MRO industry as well as for us. We are building up know-how today for the maintenance and ground processes of tomorrow.”

Meanwhile, the partnership between German start-up H2FLY, which is developing hydrogen fuel cell systems for aircraft, and a new German aircraft manufacturer Deutsche Aircraft will aim to convert a Dornier 328 aircraft for a first hydrogen flight in 2025.

The programme is expected to validate climate neutral regional air travel with up to 40 seats and the teams are planning to equip the demonstrator with a 1.5MW hydrogen system which they say will make it the most powerful hydrogen-electric powered aircraft to date. The companies will work together on integrating the power system into the aircraft as well as defining the specific technical and certification requirements for fuel cell systems in EASA’s large aircraft class.

H2FLY grew out of a partnership between DLR and the University of Ulm and its four-seater hydrogen-electric powered HY4 has already undertaken over 70 take-offs in flight campaigns. With its range of up to 750km, the company believes regional markets can be developed.

“Hydrogen fuel cell technology provides an opportunity for us to completely eliminate carbon and NOx emissions from regional flights and the technology to make that happen is closer than most people think,” said Prof Dr Josef Kallo, co-founder and CEO of H2FLY.

“Over the last 16 years we have worked hard to demonstrate our technology on smaller aircraft, completing record breaking flights based on six powertrain generations. We are pleased to be taking that to the next level with Deutsche Aircraft as we scale our efforts up to regional aircraft.”

Deutsche Aircraft says it is putting climate change at the heart of its design philosophy. “We are looking forward to partner with companies that not only share our passion for the environment but also have the technical expertise to ensure climate-optimised aviation stays safe and reliable,” said Martin Nüsseler, Deutsche Aircraft’s CTO.

The company says the higher propulsive efficiency of propeller-powered aircraft will drive a change in propulsion technology that will result in further reductions in fuel consumption and emissions.

“Combining modern propeller aircraft design with zero carbon energy sources is central to achieving climate-neutral air transportation,” added Nüsseler.

Commenting on the project, Thomas Jarzombek, Member of the German Bundestag and Coordinator of the Federal Government for German Aerospace, said: “From 2035 onward, hybrid-electric flying has to be the new standard in Germany. The German government will continue to support this path to innovation with its R&D funding programme, aiming to let the vision of zero-emission aircraft become a reality.”

Top image: Airbus